1. Field of the Invention
This invention relates to camera stabilizers, and more particularly to hand held camera stabilizers which allow the camera and operator to move while filming or taping events.
2. Description of Related Art
Advances in optical, video, and traditional photographic technologies have made high quality portable photographic equipment available to a growing number of film enthusiasts. As a result, photographers are continually creating motion pictures of increased quality and complexity. However, a problem encountered by nearly all film enthusiasts is that of shooting smooth, quality footage with a hand held camera. This problem, which is encountered when the operator tries to hold the camera steady, rotate the camera through an angle (i.e, panning), or move the camera in translation, is caused in part because of operator motion which is transmitted to the camera resulting in unwanted camera motion.
The problem of unwanted camera motion during hand held filming is especially noticeable when filming conditions require panning, moving the camera, or where either the camera or the camera operator is required to move. Turning or carrying the camera in a smooth even fashion requires a great deal of skill and experience, particularly in action scenes where the camera operator is walking, running, or riding in a vehicle to follow the subject of the film. In action situations, the already difficult task of holding a camera steady despite motions resulting from the operator's breathing, heart beat, and involuntary muscle movements, is severely aggravated by environmental conditions. As a result, footage is frequently erratic, jerky, difficult to watch and visually unappealing. Although sudden translational disturbances and unsteady camera movements contribute to this problem, angular disturbances, particularly high frequency angular disturbances, are most prevalent and are also most difficult to control.
Film makers have eliminated unwanted camera movements in most contexts by using complex camera hoists, booms and damping equipment which is not operator-held. When operator-held filming is necessary, many film makers rely on systems similar to that described in U.S. Pat. No. 4,158,488. In this system, the camera is mounted on a gimbal device attached to an articulated arm. The arm is connected to a body harness which is worn by the camera operator. Shock isolation systems in the arm and gimbal device minimize unwanted camera movement. Additionally, the system, including the camera and its associated equipment, is a relatively high mass body with relatively high angular and translational moments of inertia which help to eliminate undesirable camera movement. The harness lowers operator fatigue by transferring the bulk of the weight of the system to the operator's body. However, while the system works well, it is prohibitively expensive and complex for most amateur photographers.
U.S Pat. No. 4,206,983 also describes a body-mounted camera stabilizer. The stabilizer relies on a complex system of articulated arms and damping devices to minimize unwanted camera movement. However, it is also excessively complex and expensive for most amateur photographers.
Several camera stabilizers have been designed for amateur photographers. Such systems typically include camera carrying frames of various configurations. Some also include weights in the frame in an attempt to increase the angular moment of inertia of the camera system. However, each presently available system has several shortcomings. For example, in some systems, such as that described in U.S. Pat. No. 2,945,428, the frame encircles the body or head. Such a system is inherently dangerous, particularly in action situations where the device is most needed. U.S. Pat. No. 4,672,436 discloses a support made of a single staff and a camera supported with its lens coaxial with the holding axis. It provides yaw and pitch stability but essentially no roll stability. Roll stability is accomplished by gripping the unit with two hands at separated locations. This aggravates the problem of angular disturbances because disturbances are transmitted to the stabilizer from a point other than the center of gravity, dramatically increasing the torque and the amount of angular disturbance. Other systems, such as that of U.S. Pat. No. 2,806,416, are frequently designed to be held at shoulder height or in front of the operator. Maintaining the camera system in these positions requires the operator to hold the device with flexed muscles. As a result, the operator's muscles fatigue rapidly and contribute to camera instability.